﻿124 PROF. E. W. SKEATS ON THE [Feb. I905, 



traces of organisms are dark meandrine areas scattered through the 

 section. 



Wo. 42. From the fault-valley of Monte Cristallo, just below Tre 

 Croci. 



A compact, rather fine-grained dolomite, formerly crowded with 

 organisms, of which only the ' ghosts ' or dark outer borders can 

 now be traced. Shells and meandrine forms constitute the most 

 abundant organisms. 



Eaibl Deposits. 



Wo. 4. Red dolomite from the Schlern plateau, below Burgstall. 



A somewhat ferruginous, coarse-grained dolomite. Most of 

 the crystals have dark reddish centres, and some of the iron is 

 concentrated along definite lines or cracks. No organisms are 

 recognizable. 



Wo. 73. Below the military post, on the Diirrenstein massif. 



The section consists of a transverse section of a coral, preserved 

 in calcite and embedded in a fine-grained homogeneous matrix of 

 dolomite. 



Wo. 58. Wear the summit of the Col du Bee, between Monte Tofana 

 and Lagazuoi ; near the base of the Eaibl Beds. 



A fragmental rock, made up of rounded pieces of somewhat iron- 

 stained dolomite, together with some rounded basalt-fragments, all 

 set in a matrix of dolomite. Some crystals of clear felspar are 

 scattered through the rock. They show extinction-angles up to 20° 

 from prism-edges, and sometimes include cubes of rock-salt. 



Irregular, clear, secondary quartz fills cavities in the rock. The 

 quartz is traversed generally by almost rectangular cracks, and has 

 inclusions of gas-bubbles, and also of clear idiomorphic rhombohedra 

 of dolomite (?). 



No. 106. Just above the Schlern Dolomite, northern end of Sett 

 Sass. 



A fragmental rock, composed mainly of small pieces of a spherulitic 

 rhyolite showing an irregular radial structure. Secondary quartz 

 is present, and contains inclusions of rock-salt, gas-bubbles, and 

 dolomite (?)-rhombohedra. Felspars are also present, one of which 

 shows simple twinning, and many contain included rhombohedra of 

 dolomite (?). A fragment of chlorite, too, is present, and the rock 

 has a small quantity of a calcareous or dolomitic cement. 



Y. Organisms recognized in the Limestones and Dolomites. 



Many observers have studied the organic remains from the various 

 deposits of the Alpine Trias. Naturally, the richly-fossiliferous 

 St. Cassian Limestone has been most narrowly examined, and the 

 varying lithological and palseontological characters of the Raibl 

 deposits have also been closely studied. The Dachstein, Schlern, 

 and Mendola Dolomites have received less attention from palaeonto- 

 logists, because fossils are far less commonly found, except in those 



